Artificial hatching of monovoltine silkworm Bombyx mori L. eggs by using hydrochloric acid

Abstract

The present work was carried out to investigate artificial hatching of eggs of silkworm Bombyx mori L, Eggs were treated at 0, 12, 24 and 36 hours after oviposition by different dilutions of HCL ;1: 1.5, 1 : 2.0 and 1 : 2.5 (water to HCL in volume) at different exposure times; 5, 10 and 15 minutes. The eggs were incubated at 25°C aiming to rear the insect all over the year for different purposes. The results obtained may be summarized as follows. High hatchability percentages appeared in eggs treated after 24 hours from laying (more than 90% hatching). But when the time of immers on was prolonged to 36 hours, the percentage of hatching decreased. In the case of 0 and 12 hours, the percentage of hatching was so low. Hatchability was decreased when the concentration and the time of dipping of HCl increased, especially in the eggs with the age of 12 and 0 hour period, but hatchability increased in case of the eggs of 36 hours age when concentration and dipping time in HCl were increased. Mortality of larvae increased among larvae which were produced from eggs of 0 and 12 hour age in their second, third, fourth and fifth instars, but decreased in case of larvae which resulted from eggs treated at 24 and 36 hours age in larvae second, third, fourth and fifth instars.